How to build the GWS Pico Tiger Moth

Transcription

How to build the GWS Pico Tiger Moth
How to build the GWS Pico Tiger Moth
By ArcherAce
A Word Before We Start
The first RC airplane I ever built was the GWS Pico Tiger Moth. Even though I’m not a
regular model builder, it still should have not taken me the week to build that it did.
Other than my lack of building skill, the biggest problem was, and continues to be the
instruction manual.
At the 2004 Toledo Weak Signals Expo, I had the pleasure of talking to Mr. Linn, the
man being GWS. He promised that new manuals for all the planes they offer where in
the works. Since they have yet to materialize, and I’m about to start my fourth Tiger
Moth build, I decided to take some pictures and write this impromptu addendum to the
GWS manual.
Before I go any further, I’d like to thank everyone who has helped me over the last two
years (has it been that long?!?!) The Ezone’s RC Groups forums are an indispensable
resource when it comes to up to date info, and instant help. I couldn’t have done it
without you guys!
The Pico Tiger Moth lends itself well to modification. Some of these “mods” are
necessary. Some are purely esthetic. Whenever there is a deviation from the stock build,
I’ll make sure to note it in these instructions. If there is an optional mod, you’ll find the
symbol. The last page of this manual will be dedicated to these esthetic mods.
I believe listing the esthetic mods at the end will help your build flow, and not clutter the
instructions. I suggest that you skip to the back of these instructions when you see that
there is a possible mod. You might want to add it before you go any further with your
build!
Last, if you have anything that you think should be added or corrected, feel free to
contact me at [email protected]. Or, you can reach me through
www.rcgroups.com. My nickname there is ArcherAce.
Feel free to post and distribute this file. I only ask that you leave it as is, with my name
on it. I just spent the last 8 hours typing this, it’s the least you could do.
Lets Get Started!
The first few pages of the manual are useful the way they are. The diagrams are very
helpful to the new builder. For that reason, I include them here as they appear in the
manual. You can also find them on the GWS website.
There are a number of additional tools, and items you will need. While some of them are
certainly not necessary, they will make for not only a much nicer plane, but also a much
more enjoyable build.
As you can see, I recommend using both 5 and 15 minute epoxy to build your Tiger
Moth. There will also be a use for both odorless (foam safe) and thin (NOT FOAM
SAFE) CA.
There have been arguments that using epoxy on these planes makes for a heavy plane.
This is simply not true! As long as you use a generous amount of microballoons, the
epoxy turns out quite light. The microballoon filler also gives the epoxy some flexibility.
The reason we will not be using the supplied GWS glue is two-fold. First, it’s not really
glue. It’s contact cement. If you do decide to use it, here is how.
First smear a thin layer of glue on one of the two parts you want to join. Then, put the
two parts together to distribute the glue evenly between the two parts. Pull the parts back
apart, and put them aside for approximately 5-10 minutes. After that time, the glue will
feel dry to the touch. Pick up both parts and carefully align them and press them
together. The contact cement bonds the second that you touch the two parts together.
YOU DO NOT GET A SECOND CHANCE! Parts do not always match up as well as
they should.
The second reason is time. You want to put the model together quickly so you can enjoy
flying it. Why wait days for glue to dry?
Whichever glue you decide to use, always remember MORE GLUE DOES NOT MAKE
A STRONGER BOND! Instead of thinking “How much glue do I need”, think “How
little glue can I get away with”. This will help keep this build, and any build you
undertake, light!
Assembling The Fuselage
Locate the IPS (indoor power system) stick and the left side of the fuselage. The left side
should have the number 1 cast in the foam on the inside near where the motor mounts and
where the rudder mounts.
Trial fit the stick in the corresponding slot in the fuselage. You’ll notice that the stick
only fits one way. Pay attention to which side of the stick will be facing up. This is the
side of the stick that you will mark the thrust angle. Most every prop driven plane
requires the motor/prop to point a bit down and right. This helps counteract the rotational
torque of the motor. Setting the thrust angle will make your plane much easier to trim out
and fly.
Now that you know which side of the stick is going to face up, use your triangle to mark
a line, from back to front. The back line should be 5mm in and the front should be 4mm
in. Also, mark a line at 22mm from the front of the stick. This is where the motor should
stop when you install it on the stick. (page 5 figure 1 of your GWS manual)
Place the marked stick back in the fuselage. The line on the stick should line up perfectly
with the inside of the fuselage. If it does not, double check both your measuring, and
that you have the stick oriented correctly (5mm in the back, 4mm in the front). If these
are both correct, use your sanding block to carefully sand the stick to bring the thrust
angle into alignment. Now is also a good time to make sure you motor will slide onto the
stick. If it will not slide onto the stick, use your sanding block to sand away just enough
of the stick to allow for a tight fit of the motor. (page 5 figure 2 of your GWS manual)
Once this is correct, remove the motor from the stick and set the stick aside.
From the plastic parts frame, locate part number 5. Use your #11 hobby knife to carefully
cut the part from the frame. This part will be used as your tail skid.
If you intend to fly your Tiger Moth outdoors, do not cut the skid as shown in the GWS
manual. When the skid drags on the pavement (on takeoff and landing) the asphalt will
grind away the skid. After one season of flying, you’ll be luck to have a skid left! The
mod listed at the end of the manual addresses this.
Trial fit the skid in the cutout in the left side of the fuselage. Check the GWS manual
again to be sure you have the skid oriented correctly. (page 5 figure 3 of your GWS
manual)
Next, locate both the strut and cowl mounts. They are the small punch outs in the main
wing strut set. You should have four cowl mounts and two strut mounts
When you’re sure the ips stick and tailskid fit correctly, mix up a bit of 5 minute epoxy
and microballoons. Glue these into the left side of the fuselage. Glue two cowl mounts
and one strut mount to the right side of the fuselage. After a few minutes the epoxy will
get tacky. When the ips stick and the tail skid tack up, use the last bit of epoxy to glue
two more cowl mounts, and one strut mount to the left side of the fuselage.
Once the glue is set, use your pin drill to carefully drill a hole in the sides of the fuselage
where the control wires exit. (page 5 figure 3 of your GWS manual). When drilling work
very slowly. The drill will want to tear the foam more than it cuts it.
Next, we’ll glue the two halves of the fuselage together.
Start by dry fitting the two halves together. It’s not unusual for the two halves of the
fuselage to be bowed away from each other. This doesn’t make any difference as to how
they will fit.
What’s important is that when the two halves are pressed together they match up without
any large gaps. A small gap near the cockpit isn’t unusual. You should only be
concerned if you have a large gap. If you can’t press the two halves together, use your
sanding block to carefully match the parts.
Tear off four strips of masking tape, about 10 inches long. Take one of the strips and tear
it in half, so it’s about an inch wide.
The GWS manual tells you to use “paper tapes” to hold your fuselage together while the
glue is drying. The problem with that is most tape will pull the yellow paint right off
your model! If you try to use a rubber band, it will leave marks in your fuselage. We
are going to hold our fuselage with tape, but we are going to wind it backwards.
Start by holding the two halves of the fuselage together. Line up the cowl area, and wrap
the longest piece of tape around the forward edge of the fuselage.
You can see that my left thumb is holding the tape until the other end comes around and
overlaps it. The sticky part of the tape should be facing away from the plane! Wind the
tape snug, not tight!
Wrap another piece of tape around the fuselage behind the cockpit using the same
technique.
Your third wrap should be a bit in front of the rudder cut out.
Use the last, small piece of tape to wrap around the back edge of the fuselage.
Here’s how it looks when it’s done. Remember, the sticky side of the tape is facing out!
Starting with the small wind on the end, slide the tape “ring” off the fuselage. Next
remove the tape ring from just in front of the rudder area. After that, the ring from behind
the cockpit. Finally remove the cowl tape ring.
Examine the inside of the fuselage and make a mental note of all the mating surfaces.
Also, notice the tailskid cutout in the right fuselage. If you’re using the stock GWS
tailskid it’s important that you apply glue to that cutout. You’ll also want to apply glue to
the motor stick cutout on the right fuselage.
To join the fuselage, it’s best to use 15 minute epoxy this give you plenty of time to apply
the tape rings and be sure everything is lined up. If you’re confident you can get the two
halves aligned quickly, and then use the 5 minute epoxy.
Before you mix up the epoxy, have a paper towel, soaked with rubbing alcohol ready.
This is used to clean up any epoxy that squeezes out. If you are building a yellow Tiger
Moth, test the alcohol in an inconspicuous place to be sure that it doesn’t remove the
yellow paint. I haven’t built a yellow Tiger Moth in some time so I can’t test this to be
sure it’s ok!
Mix up a large batch of epoxy and microballoons. Make sure you’ve mixed up more than
you need. It’s better to have to much, then not enough. There won’t be time to mix up
another batch.
Using a toothpick, or similar applicator, sparingly apply your epoxy and microballoon
mixture to all mating surfaces on one side of the fuselage.
Align the other half of the fuselage. Starting with the cowl tape ring, slide it onto the
cowl area. This time, push it as far back as it will go. The tape will tighten up against the
taper of the cowl area. Be careful not to push any of the rings so far back that you dent
the foam. That much pressure isn’t necessary. In order, slide the cockpit ring, the rudder
cutout ring, and the back of the fuselage ring onto the fuselage. Slide each ring up a little
farther than where they were when you made them.
Using your paper towel and rubbing alcohol, wipe away any excess epoxy.
Hold the fuselage until the epoxy sets up. Use its drying time to make sure that
everything is aligned. Pay special attention to the cockpit area. If your fuselage halves
are a bit out of alignment after the glue has set, you can always sand them back into
shape. However, the cockpit area is difficult to fix. Usually, you’ll have to hold the
cockpit area together until the epoxy dries.
Once the glue has dried, gently twist and pull on the tape rings to slide them off the
fuselage. The masking tape I use is used in auto painting. I don’t know if there are
different types of masking tape, but this brand (Scotch) has never stuck to any of the
epoxy that has squeezed out. This shouldn’t be an issue though. You didn’t use enough
epoxy to have any squeeze out. Did you?
Building The Wings
Lower Wing
Locate the plastic wing joint cover. If you look at the top of the cover, you’ll notice an
indentation running around the top. This is where you’ll cut. Here is a picture for
reference.
You can use standard scissors to cut this out, but it’s best to use a set of curved scissors.
These curved scissors can be purchased at any hobby store for a nominal fee. The curve
in the blades makes it much easier to cut out any plastic parts. If you intend to build
models, this is a must have item.
Next, we will set the dihedral in the lower wing. Dihedral is the angle in the wings from
the fuselage. It’s the slight “V” shape made by bending the tips of the wings up. It is
important to have dihedral in your wings, as it contributes to the overall stability and
turning ability of your Tiger Moth.
To set the wing dihedral, we will not be using the tape provided in your kit. What you’ll
need is something heavy enough to hold one side of the wing flat against your work
surface, and something to prop the other side of the wing up while it dries. I always use a
two liter pop bottle half filled with water, and four CD jewel cases.
Start by mixing up a batch of 5 minute epoxy and microballoons. Fold the wing back on
itself, so the center seam opens up. Do not fold it so far that you crack the seam!
Apply a liberal amount of epoxy into this center section. Try to put it all right in the
middle of the seam.
Place the lower wing on a flat surface and lay the pop bottle flat on one side of the wing.
Make sure that the bottle is holding the wing flat, but not crushing the wing! I’ll usually
flatten my bottle a bit then put the cap on. This takes the roundness out of the plastic
bottle and keeps it from rolling off the wing.
Stack up your four CD cases, and slide them under the opposite side of the wing. Here’s
how it should look. I’ve left the CD cases hanging out, but you should have them
completely under the wing. That way you’re sure to get even pressure across the joint.
The wing will dry straight.
The GWS instruction manual (page 6 figure 11) shows that with one side of the wings
flat on your building surface, the other side should be set to a height of 80mm. Slide the
CD cases toward the pop bottle until the wing tip is 90mm off the building surface. The
extra 10mm allows for some “droop” in the wings once the glue cures.
Located in the same bag that held the wing joint cover, you’ll find two pieces of double
sided tape. Apply this tape to the bottom of the wing joint cover per the GWS manual.
(Page 6 figure 10) and install the wing joint cover.
Upper Wing
The upper wing builds almost identical to the lower wing. Again, we will not be using
the GWS tape method, but epoxy to set the dihedral.
Just as you did for the lower wing, mix up a batch of 5 minute epoxy and microballoons.
Apply the epoxy into the middle of the seams on the upper wing.
Set something with enough weight to hold the wing flat between the epoxy filled seams.
I’m using a half filled bottle of rubbing alcohol. Again, be sure that it is heavy enough to
hold the wing flat, but not heavy enough to damage the wing.
Take your CD cases, and slide them under each side of the wing at the same time.
The GWS manual tells us that with the center section flat, each wing tip should be raised
to 38mm. Using your CD cases, adjust the height of the wingtips to 46mm. Again, the
extra height allows for droop.
As a note, I realize that my measurements would be off since I have the center section on
a mat. I’ve allowed for the thickness of the mat. I just couldn’t have taken any decent
pictures of a white plane on a white building table so I’ve tried to use the mat as a
background.
When the epoxy cures, you’re done with the wing build. There is no need to apply the
PVC wing joint tape to the upper wing. (Page 7 figure 14)
Horizontal Stabilizer and Vertical Fin
Locate the foam sheet that contains the horizontal stabilizer and vertical fin. Carefully
remove them from the foam. Save the foam scrap for use later.
Look closely at the stabs and you’ll see that one side one side is flat, the other is grooved.
The grooved side of the horizontal stab is the bottom. We’ll build this one first.
Using both hands, carefully flex the elevator on the horizontal stab to “loosen up” the
foam. (The elevator is the part that moves. The stabilizer is the part that gets fastened to
the fuselage)
Flex one side, then the other. Try not to crack the foam joint. If you do, it won’t make
much of a difference, but its best as one solid piece.
Next, locate the clear tape that is provided in the kit. It’s on the decal sheet. Using the
longest piece lay the tap across the flat side of the seam.
Once you have the tape secured, continue to flex the seam back and forth until it loosens
up.
Repeat this process for the rudder. Notice that the rudder’s seam in on both the vertical
stabilizer and below it where it fits into the back of the fuselage.
Painting
If you’re building a white Tiger Moth, now it the time to paint it. Whatever paint you
decide to use, test it first on the scrap foam left over from the stabilizers. Most spray
paint eats foam, so be careful!
Before you paint, it’s best to lightly sand the fuselage. Use a sanding block and fine
sandpaper to remove the mold marks. Also take this opportunity to sand the two halves
of the fuselage into alignment. When you’re done sanding, wipe the plane down in
rubbing alcohol to remove any dirt and oil.
Painting the Tiger Moth isn’t so much painting as it is dusting. When finished, you
should still be able to see the white foam under the paint. Paint adds a lot of weight. If
you try to cover the white completely, you’ll turn a nice floating plane into a flying pig.
If you can, try to incorporate the white of the foam into your paint scheme.
If you paint with spray cans, hold the can as far away from the plane as you can and
allow the paint to fall onto the plane. Spray paint contains acetone. Acetone dissolves
foam. If you hold the can as far away from the plane as you can when you spray, it gives
the acetone a chance to evaporate before it touches your plane.
Details can be added later with a sharpie marker. While markers don’t look as good as
paint, they add virtually no weight.
Installing The Tail Feathers
To install the horizontal stabilizer, you’ll need to find the exact center. The notches in
the center of the stabilizer and elevator are 3mm and 18mm respectively. Half of that
would be the center of the stabilizer. Working on the side that the tape is on (the top)
measure 9mm across the bottom opening and 1.5mm across the top. This is the center of
the stabilizer. Draw a line to mark the center.
Now, flip the assembly over and place a small mark at 9mm on the bottom of the
elevator.
Trial fit the assembly to the fuselage. If it is crooked, use your sanding block and
sandpaper to align the halves.
Mix up some 5 minute epoxy and microballoons. Lightly coat the mounting surface on
the fuselage with epoxy. Align the horizontal stabilizer, with the line up, with the center
of the fuselage. Use the fuselage seam as a guide. Once you get the stab lined up, use
pins to hold it in place. Carefully flip the fuselage over and look at the mark you made
on the bottom of the elevator.
Looking through the rudder mounting slot at the back of the fuselage, make sure your
mark lines up with the fuselage seam. This ensures that your stabilizer is straight.
After the epoxy has cured on the horizontal stabilizer, remove the pins and trial fit the
vertical stab and rudder. Once you are satisfied with its fit, mix up another batch of
epoxy and microballoons and secure it to the top of the horizontal stab. (page 9 figure
25) and the slot in the back of the fuselage. Be sure that you do not push the stab to far
into the fuselage! You want the hinge line to fall just behind the fuselage.
While the epoxy is drying, use your triangle to make sure the vertical stab is truly
vertical.
You can see that a spring clap not only holds the bottom of the vertical stab while it dries,
but also act as a stand for the plane. Remember when you’re setting the angle of the
vertical stabilizer that you are in fact using the vertical stabilizer and not the rudder! The
rudder is the part that moves, the vertical stab doesn’t. Place your triangle on the stabs,
not the moving surfaces!
Wing Mounts
This is very straight forward. Use a drill, or your hobby knife, to open up the holes in the
side of the fuselage.
Insert the supplied dowel rods into the hole making sure that there is an equal amount of
dowel showing on each side of the plane.
Secure the dowels with a few drops of foam safe CA
Motor Cowl
Using your curved blade scissors, follow the indentation and cut out both halves of the
motor cowl.
Looking at each side of the cowl, you’ll see little dot like indentation. These dots are
where the screws go to mount the cowl to the fuselage. Put the blade of your hobby knife
on these indentations, and spin the knife to drill a hole in the cowl. Do not make the hole
to big. A smaller hole will help hold the screws in place.
Place one half of the cowl up to its respective side of the fuselage. Line up the holes you
just made in the cowl with the cowl mounts that you glued in place. While holding the
cowl and fuselage with one hand, use your hobby knife to drill a starter hole in the cowl
mount. This hole doesn’t have to go all the way through the cowl mount. It’s just used
to get the screw started. Install the screw and repeat the process for the other three cowl
screws.
Once you have the cowl mounted, you’ll see a bit of overlap between the two cowls.
GWS recommends that you use this overlap to glue the two cowl halves together. We
won’t be doing that.
Using Scotch brand crystal clear tape, pull a piece that is longer than the top of the cowl.
Do not use the cutter on the dispenser to cut the tape. Instead, use a pair of scissors to cut
the tape. If you use the cutter, you get a jagged edge on the tape. This jagged edge will
show. If you use scissors to cut the tape, the clean cut edge will be almost invisible.
Lay your scissor cut piece of scotch tape along the cowl seam from front to back. The
seam will not be right on the center line of the plane. There is a way to make your seam
line up with the center line of the plane, but this is unnecessary. Once the cowl is
painted, the seam will blend in nicely.
Next, remove the four screws holding the cowl in place. Open the two cowl halves up,
bending them along the tape hinge line. Using your curved blade scissors, remove the
part of the cowl that is overlapping on the inside of the cowl.
Wipe the inside of the cowl with rubbing alcohol and allow it to dry. When it’s dry,
lightly dust the inside of the two cowl halves with spray paint.
When the paint had dried, install the IPS motor on the stick, (page 10 figures 29-30) and
re-install the cowl.
Main Landing Gear
Locate the wheel rims and the rubber o-rings that are to be the tires.
Slip the o-rings onto the wheels and secure them with thin CA glue. (Page 11 figure 36)
Locate part #4 from the plastic parts frame and cut out two of them with your hobby
knife.
The spokes of the GWS wheels are made to act as a shock absorber. To this end, they
must be installed properly. If you look at page 11 figure 36 picture 2 of your manual,
you’ll notice that the wheel there is facing forward, if the plane it were mounted on were
facing to the right. Notice how the wheels are oriented in the below picture. There
wheels are mounted in the proper direction.
Once you are sure you have the wheels oriented correctly, use the #4 fasteners to secure
them to the landing gear.
The problem with the GWS landing gear is that on a hard landing the landing gear wire
flexes outward, into the foam. After a few hard landings, the sides of your fuselage will
have crack in them from the landing gear. This mod fixes that.
Using dental floss, or a heavy sewing thread, begin to wrap the thread around the landing
gear just above where the gear would fit into the fuselage. Wind the thread back and
forth, in and out of the gear. After 8 or so winds, tie the ends of the string together and
cut off the excess ends. Gather the thread up at the base of the gear, just before it turns
down into the legs that support the wheels. Here is how it should look.
Open up your thin CA, and put a few drops onto the thread. Allow it to wick into the
thread and dry.
After it has dried, carefully bend the landing gear back into shape. You should be
bending the gear right at the thread. You want your gear to look like this when you are
done.
Insert the landing gear into the landing gear slot, and make sure that it fits properly.
Once you are satisfied with the fit, remove the gear and put some epoxy and
microballoons along the bottom of the landing gear slot. There is no need to put epoxy
on the sides of the landing gear slot. The landing gear will never touch the sides of the
fuselage anyway. Push the landing gear back into the slot, seating it at the bottom of the
slot. Add a little more epoxy along the wire to make sure you get good adhesion.
This mod transfers the force of landing off the sides of the thin fuselage walls to the
thicker top of the fuselage.
Your Tiger Moth will not stand on its own two feet!
Hooking Up The Controls
The diagrams in the GWS instruction manual do a good job of showing where and how
the gear hooks up. There are a few things that should be addressed.
Before mounting the servos, sand off the round mold marks inside the fuselage. You
want the servos to sit flat against the fuselage.
The servos mount fine with the supplied double sided tape, usually. As an extra bit of
caution, you should use a few drops of hot glue to help secure them. If you don’t have a
hot glue gun, wrap the servo in tape and epoxy it to the fuselage. This way you can
remove the servo from the plane later.
If you’re new to Z bends, check out the
pushrod system that is hard to beat!
section at the end. Du-bro makes a micro
The GWS control horn works well, but over time the retainers loosen up. This makes
control difficult if not impossible. To remedy this, run a small bead of hot glue down
each side of the retainer where the horn comes through. If you don’t have a hot glue gun,
a drop of foam safe CA will work.
Remember too, that the control horns mount a certain way! They holes on the horn
should be located over the hinge line. They are bent the way they are for a reason!
Route the antenna out behind the back of the wing saddle. (Where the wing meets the
fuselage) Run the antenna along the bottom of the fuselage, to the tailskid. Use your
hobby knife to drill two small holes at the top of the tailskid. Weave your antenna wire
through these holes. It will hold your antenna tight and keep it out of the control
surfaces.
Wing Assembly
Start the wing assembly with the struts.
For some reason, people seem to think that these struts need to be replaced with wooden
ones, or at least sandwiched between two pieces of wood. Adding wood to this plane
would add unnecessary weight. Here’s a better idea that no only reinforces the wing, but
looks great too!
Start by using your #11 hobby knife to drill four very small holes in the corner of each
strut.
Here is how they look when they are done. Along with notes on how they are oriented.
(Sorry I took the pictures upside down. Refer to page 14 figure 42 picture 5)
After you get the holes drilled, you can paint the strut.
If you refer to page 13, figure 41 you’ll find some excellent pictures on how to install the
struts to the wings. If you look carefully on the top of the bottom wing, and the bottom
of the top wing, you’ll find four small indentations. These indentations are where the
struts mount. However, some clarification on the positioning and installation of the struts
are in order.
When you glue the struts into the wing, push the tabs on the struts into the wing skin.
You might have to use your hobby knife to cut a slot for them to fit into.
Once you get the slots cut, tear off a number of pieces of masking tape and have them at
the ready. Double check that you have the strut orientation correct. If everything dry
fits, mix up a batch of epoxy with microballoons.
Starting with the lower wing, place a small dab of epoxy on each indentation where the
strut is to be mounted. Push the strut into the indentation and secure it with masking
tape. You may have to hold it for a few minutes until the epoxy tacks up. After the glue
cures, go along the bottom of the strut and secure the rest of it to the wing with drops of
foam safe CA.
The top struts should line up along the outside of the seam on the top wing. In the picture
below, you can see where I have a gap between the seam and the strut. After the glue has
dried, you can go back and fix this with foam safe CA.
Since the inside struts must “bow” to touch the seam, you must hold the strut in place
until it dries. It is important that the struts be glued securely to the seam.
Once the glue cures on the top wing struts, attach the outside struts to the upper wing.
There is no easy way to do this. You have to hold the struts straight while they dry as
you support the weight of the wings.
Attaching The Wings To The Fuselage
Refer to page 14 figure 42 of your GWS manual. The pictures here are excellent. The
only recommendation I have is that when you put the strut screws into the mounts, you
first start a pilot hole with your hobby knife. Like the cowl mounts, the hole doesn’t need
to go all the way through. It only needs to be deep enough to allow the screw to bite into
the plastic.
Installing Flying Wires
This mod should have been part of the kit the whole time. Without installing flying
wires, you’ll rip the wings right off your Tiger Moth on the first loop. Even if you never
intend to loop your Tiger Moth, the flying wires do more to improve the looks of your
plane than any other mod.
Start by pulling off a few feet of either dental floss or heavy thread. Use whatever color
you’d like. I’m using the same heavy white thread that I used on the landing gear.
Tie the thread into a knot at position #1 and apply a single drop of thin CA. Remember
thin CA is *NOT* foam friendly. So, be sure you don’t get any on the wings! Eyeball a
straight line from position #1 to position #2 on the lower wing. You’ll notice that the
wing joint cover hangs out a bit from under the fuselage. This is what you want. Use
your hobby knife to drill a small hole through the wing joint cover and through the
bottom wing. Fish the string through that hole and out the bottom of the wing. Again,
eyeball a straight line from position #4 to position #3. Use your hobby knife to again
drill a hole through the wing joint cover. This creates the hole for position #3. Fish the
thread from position #2, up through the bottom of the wing, and out the top of position
#3. After that, follow the pattern all the way to position #9. Once you get to position #9,
go back through and take any slack out of your thread. You don’t want the thread guitar
string tight, just snug. A bit of play is fine. Once you are satisfied with the tension on
the thread, put a drop of thin CA on position #9. Tie off the string that is left at position
#9 and cut off any excess thread. Repeat for the other wing.
Du-bro makes a fine line of accessories for park flyers. Their tail wheel assemblies work
well on the Tiger Moth. A real tail wheel will eliminate the cheesy looking control horn.
For the ultimate in tail wheel assemblies, check out LighterRC’s steer-able tail assembly.
It puts the stress on the fuselage, but hooks to the rudder. Nothing looks cooler than
taxiing out to the runway!
The stock GWS wheels are very weak. Replace them with Du-bro’s 2” micro light
wheels. To secure them to the landing gear, cut a small circle out of paper and push it
onto the landing gear wire. Secure the paper with a drop of epoxy. After the epoxy dries,
use a marker to color it black. I’ve never had a wheel pop off!
North East Sailplanes sells a nice super light wheel. It’s a bit big at 2.5”, but they look
and work great!
Making Z bends to secure your control wires is a real pain. It also makes adjustments
difficult. To avoid this hassle, check out Du-bro’s RC micro pushrod system.
Need more mods? Check out Ezone’s warehouse of information on the GWS Tiger
Moth!
Prop Savers
If you crash, or have a less than perfect landing, the orange GWS props are suppose to
snap in two. This is both good, and bad. Good, because it prevents the prop from acting
like a giant lever and bending the gearbox output shaft. It is bad because you’ll go
through a ton of props. To prevent this, you should install a prop saver.
This version of the prop saver was first posted on Ezone by t j-rome. It’s takes 2 minutes
to make, and works very well. The only drawback is that it’s almost impossible to use a
spinner with it. A small price to pay to save a fortune on props though!
Begin by finding an extra servo horn. For this example I’m using a one with four arms.
A two arm horn works just as well. You’ll also see in the picture that we use two GWS
prop shaft washers, two GWS prop shaft nuts, and a couple of small rubber bands. The
rubber bands I’m using can be found in the hair care section of any store. These rubber
bands are used to hold very small hair braids (cornrows).
The next step is to sandwich the servo horn between the washers, held in place by the two
nuts. The nut that is on the end of the prop shaft should have no more than a few threads
sticking out the end. If you turn it down to far, the prop will not be able to fold.
Using a pair of needle nose pliers, bend two opposing arms back toward the motor. They
bend quite easily, and will retain the bend well.
Finally, put the prop on the end of the shaft and secure it with two or three small rubber
bands. To test your prop saver, simulate a prop strike by pushing the prop down onto
your work table. The prop should fold over.
Always check the condition of your rubber bands before you fly. They do tear and
deteriorate with use. Losing a prop in flight is just as bad as breaking a prop!
Making Pilots
Every plane needs a pilot, and the Tiger Moth is no exception! If you have a printer and
a paint program you can add any pilot you want to your Tiger Moth. Here’s how.
Cartoon characters work best. But, you can use any picture you have. For this Tiger
Moth, I decided to use Garfield.
Start by opening up the picture in your paint program. Using the resize option, scale the
picture so that it looks right in your plane. Don’t worry about making it true scale. What
you’re after here is more cartoon scale! Resize and print your picture until you’re happy
with the size. Then print out it out. Go back into your paint program and chose the
mirror option. Print that out also.
Next, cut out one of the pictures. Don’t worry about trimming it around all the details.
You can see in the picture below that I left Garfield’s whiskers as one solid piece.
Rough cut the other picture out. Using a glue stick, attach it to a disposable foam plate.
Use your #11 hobby knife to cut the picture out of the foam.
Now, flip the picture with the foam backing over and glue the other picture to it. You
might have to use your hobby knife to fine tune the fit. Here’s how it looks.
To secure the pilot to the plane, a dab of epoxy on the bottom of the pilot is all it takes.
When you line up your pilot in the cockpit, be sure to set him up parallel to the seam in
the fuselage! If you get him crooked he’ll no longer be a pilot, but a rudder!
Here are a few more pilots to get you started. I’ve also included a picture of an
instrument panel. You’ll have to trim it to fit. Use a glue stick to secure it to the cockpit.